What are your views on the tradition of automatically granting all embassy and consulate personnel, "diplomatic immunity" from prosecution?

I understand that the practice was instituted to prevent blackmail against the personnel, and that the only remedy a government has against them (if they have committed a crime), is to expel them from the country.

There have been case histories of embassy/consulate personnel commiting all kinds of crimes, from illegal narcotics to premeditated murder, with impunity.

I know that the reason the tradition exists, is to prevent an unfriendly nation from framing an Ambassador with phony “evidence,” but when a person can come into our country wearing that legal “armor plating,” get by with anything they wish, and the worst thing that can befall them is expulsion, then perhaps the rules on how this protocol is universally applied should be both re-examined and refined.

Your thoughts?